FR2610468A1 - RECORDING AND RESTITUTION SYSTEM ON MAGNETIC STRIP - Google Patents

Abstract

THE INVENTION RELATES TO THE RECORDING AND RESTITUTION OF VIDEO SIGNALS ON A MAGNETIC TAPE. ACCORDING TO THE INVENTION, A HIERARCHY OF VIDEO STANDARDS ARE SHAPED INTO A RECORDING FORMAT FOR VIDEO RECORDING AND RESTITUTION SYSTEMS TO OBTAIN PERFORMANCE FLEXIBILITY, RELATING TO STUDIO AND PORTABLE TELEVISION RECORDING EQUIPMENT; THE FORMAT DIVIDES THE BAND INTO A NUMBER OF LONGITUDINAL SEGMENTS, EACH SEGMENT BEING ASSIGNED TO TRACKS WHERE FULL FRAME INFORMATION S1-S3, M1-M3, 126, 127, 129 IS RECORDED AT A FRACTIONED RESOLUTION EQUAL TO THE QUOTIT OF ONE DIVIDED BY THE NUMBER OF LONGITUDINAL BAND SEGMENTS. THE INVENTION APPLIES IN PARTICULAR TO TELEVISION.

Description

Although many different formats of

  are well known for use in video tape systems that include recording and / or playback units, each of these systems is designed to use only one format. Therefore, there is no compatibility between systems having different recording formats because a tape recorded by one system can not be rendered in another system. If high quality performance is to be achieved, a recording format requiring intensive band consumption and a complex signal processing circuit must be used, which then becomes very troublesome in a recording equipment.

  portable. However, the simplification of the format of

  recording to gain compactness in portable recording equipment by reducing tape consumption and circuit

reduced performance.

  It has been proposed to use a hierarchy of digital television standards where a higher bit rate system would be available to achieve the high quality performance required for studio equipment and a lower rate system would be available. to achieve the compactness of the portable equipment. Such a hierarchy for the Y, I, and Q components of a television signal allows the higher rate system by sampling the components at the 4: 2: 2 ratio, respectively, and allows the lower rate system by sampling the ratio components. of 2: 1: 1, respectively. For example, in a standard

  commonly considered, a sampling frequency is used.

  13.5 MHz corresponding to a level of 4 in the hierarchy, and therefore the levels of 2 and 1 would represent frequencies of 6, 75 and 3.375 MHz, respectively. While such hierarchies provide greater flexibility between studio and portable recording equipment, the individual recording formats for higher and lower rate systems are not easily interchangeable by the fact that a tape recorded by system can not be returned directly to the other system. To convert the recording format of one system to the recording format of the other, the recorded information sampled at one hierarchy level must be rendered, transcoded to the other hierarchy level and recorded again

or otherwise transmitted to the studio.

  A multiple recording format for a video tape recording and playback system is provided where the tape is laterally divided into a number of longitudinal segments, a given segment being associated with tracks in which a double frame information is recorded at a split resolution so that different bit rates or formats are available for different aspects of the system such as studio recording equipment and

portable respectively.

  The invention will be better understood, and other purposes, features, details and advantages thereof

  will become clearer during the description

  explanatory text which will follow with reference to the accompanying schematic drawings given solely by way of example illustrating several embodiments of the invention and in which: FIG. 1 illustrates an embodiment of a multiple recording format according to the principles of the invention; FIG. 2 illustrates the sequence of Y, I and Q samples to be recorded in the tracks of each longitudinal segment of a magnetic tape having the multiple recording format illustrated in FIG. 1; FIG. 3 schematically illustrates an exploratory apparatus used to explore tracks according to the multiple recording format illustrated in FIG. 1; FIG. 4 schematically shows an arrangement for directing the image elements of the Y, I and Q components towards each of the transducers of FIG. 3; FIG. 5 illustrates a multiple recording format according to one aspect of the invention, which is adapted for use by a portable tape unit; FIG. 6 schematically illustrates the transducer arrangement on an analyzer of a portable unit adapted for use with a multiple recording format according to one aspect of the invention; Fig. 7A shows a winding of the strip and Fig. 7B illustrates the locations of the transducers on an analyzer for exploring or analyzing the tracks according to the multiple record format illustrated in Fig. 7C; FIG. 8A illustrates a tape winding and FIG. 8B illustrates the locations of the transducers on an analyzer for analyzing the tracks according to the multiple recording format illustrated in FIG. 8C; Figures 9 and 10 illustrate re-format systems of the recording and playback image elements respectively adapted for use with the recording formats of Figures 1, 5, 7C and 8C; FIG. 11 shows another embodiment of a multiple recording format according to one aspect of the invention; FIG. 12 illustrates, in block diagram form,

  a recording / playback system capable of recording

  tring and rendering a television signal in the format illustrated in Figure 11; and FIGS. 13A-13I illustrate a diagram of the times useful for explaining the operation of the system of the

figure 12.

  In digital video tape recording and playback systems, the recorded information is commonly related to each image (i.e., television frame) by a grid of samples which are to be viewed in one video. double frame. To give a portable equipment more compactness, while allowing quality performance with studio equipment, a multiple recording format is disclosed for a digital video recording and playback system. In this multiple recording format, the band is laterally divided into a number of longitudinal segments, each segment being assigned to a double frame information of record at a partial or fractional resolution of the image elements equal to the quotient of one divided by the number of the amount of longitudinal segments of the band. The video signal is first digitally inputted by sampling the picture elements at a predetermined frequency and these picture elements may refer to the composite or component video information. Each image element is directed by a transducer, at a particular track in one of the longitudinal segments, and these tracks may be disposed in each segment along the direction of travel of the strip or at a certain angle across the direction. of the course of the band.

  A preferred embodiment of a recording format

  According to the invention, FIG. 1 shows the Y, I and Q components of the video information. The longitudinal tracks 8, 9, containing for example the audio and reference signals of FIG. 1, are explored or analyzed on the band 5 by a fixed transducer head 310 of FIG. 3. The Y, I and Q components are sampled at a conventional ratio of 4: 2: 2, respectively, as illustrated in FIG. 2, for a scan line of a frame. On the other hand, the band 5 is subdivided only into two longitudinal segments 6 and 7 and the frame information doubles to half the resolution is recorded

  in each longitudinal segment of the strip. As a result

  two tracks of Y, a track of I and a track of Q are arranged in the four-track sections of each longitudinal segment and each of these tracks is explored in the direction of travel of the band in a helical pattern. As shown in FIG. 3, each track of the four-track section is simultaneously scanned by separate transducers Y1, Y2, Y3, Y4, I1, I2, Q1 and Q2 on a rotary analyzer 300 driven by a motor 312 and

  314. The band receives a movement of trans-

  The invention is directed to a capstan 316 comprising a capstan 316 in an arrangement familiar to those skilled in the art. Since the transducers are placed under the band 5 in FIG. 3, they should be represented by broken or dotted lines, but because of their small size they are shown in solid lines in the interest of clarity. A web winding of about 270 is shown in FIG. 3. However, any winding angle can be used, even an omega winding of substantially 360. In addition, each 4-track section could include information related to a simple frame in a format familiar to those skilled in the art. For each line of exploration of the frame of the video information, the track Y1 comprises the picture elements of Y 1, 5, 9, 13, and so on; track Y2 comprises the picture elements of Y 2, 6, 10, 14 and so on; track Y3 comprises the picture elements of Y 3, 7, 11, 15, and so on; track Y4 includes picture elements of Y 4, 8, 12, 16, and so on; the track I1 contains the image elements of I 1, 3, 5, 7, and so on; track 12 contains the picture elements of I 2, 4, 6, 8, and so on; track Q1 contains the picture elements of Q 1, 3, 5, 7, and so on; track Q2 contains the picture elements of Q 2, 4, 6, 8, and so on. With this recording format, the video information can be recorded at full resolution on both longitudinal segments of the tape with a studio recording unit for which compactness and portability are not of paramount importance or the half-resolution on a single longitudinal segment of the tape with a portable recording unit for which compactness and portability are of paramount importance. To record the video information at half the resolution in the separate longitudinal segments of the band, the Y, I, and Q components could be organized in many ways other than the manner described above with respect to Figure 1. For example, video information relating only to the lines of

  odd number frame scan could be saved

  in a longitudinal segment of the tape while the video information pertaining only to even-numbered frame scan lines could be recorded in the other longitudinal segment of the tape. Likewise, video information relating only to odd-numbered single frames could be recorded in a longitudinal segment of the tape while video information relating only to single-even frames could be recorded in the other segments. lengths of the band. Furthermore, the inventive concept disclosed in US Patent No. 4,393,414 issued July 12, 1983 and entitled "Interleaved Recording Format for Digital Video" could be used with the concept of the present invention by recording each of the element patterns. nested on a chessboard illustrated in Figure 1 of this patent, in the longitudinal segments separated from

  band of Figure 1 of this application.

  As previously explained with reference to FIG. 3, those skilled in the art will readily understand that transducer means are provided on the rotary analyzer 300 for each of the Y1, Y2, Y3, Y4, II tracks. Q1 and Q2 in the helical pattern of Fig. 1. An arrangement for directing the image elements of the Y, I and Q components to each of

  transducers on this analyzer 300 is shown in FIG.

  As the particular recording format chosen might

  have any number of tracks allocated to each of the

  This arrangement will be described for both the 4: 2: 2 recording format of FIG. 1 and the general situation in which the number of different tracks is not limited. The image elements of

  each component of the signal is directed to switching

  10, 12 and 14 which relate respectively to

  with components Q, I and Y. While switching

  10, 12 and 14 are illustrated as mechanical switches, it will be readily understood that switches

  electronic equivalents will be used in practice.

  Each switch 10, 12 and 14 has a number of output positions, equal to the number of format tracks allocated to its signal component. Each output of the switches 10, 12 and 14 is directed in a known manner to a track on the recording medium by one of the transducers shown in FIG. 3. Each of the directional positions of the switches 10, 12 and 14 is individually controlled by the count at the output of metersmodulo 16, 18 and 20, respectively. Each modulo counter 16, 18 and 20 has a number of count outputs equal to the number of format tracks allocated to the signal component of the switch 10, 12 or 14 that it controls and also a starting programmable counting output when the nature of the particular format chosen requires it. Since each of the components Q and I is allocated only one track in the 4-track sections of each longitudinal segment of recording format band of FIG. 1, the modulo counters 16 and 18 could be flip-flops in FIG. material arrangement. Each modulo counter 16, 18 and 20 is driven by the clock signal at the component element frequency

  the signal to which its switching

  For example, a clock signal 22 representative of the frequency (13.5 MHz) corresponding to the hierarchy level of "4", is directly applied to drive the modulo counter 20. The signal of FIG. clock 22 is applied by a division unit 24 by 2, thereby deriving the frequency level "2" required to drive the modulos 16 and 18 counters.

  The modulo 20 meter is of the program start count type.

  mable. The horizontal synchronization signal is applied to the starting count input of each modulo counter 16, 18 and 20 so that the recording of each scan line of a frame starts with the first picture element Y of that frame. line. Each switch 10, 12 or 14 is placed at a different position of the track

  for each exit account of its modulo res-

  16, 18 or 20 and the image elements of the components Y, I and Q are thus directed to the designated tracks

  in the different longitudinal segments of the strip.

  Those skilled in the art will also readily understand that the switching arrangement for rendering an embodiment of a particular recording format is essentially the inverse of the particular switching arrangement chosen for the recording. of this format and therefore this

  restitution switching is not shown in the

  the end of brevity. Accordingly, the playback switching arrangement for the recording switching arrangement of Fig. 4 will comprise a separate switch for receiving each of the picture elements of the Y, I and Q components through a track transducer of the band and a modulo counter to control each switch for the reconstruction of the appropriate feedback signal. Of course, modulos counters will be attacked by the arrangement of horizontal synchronization signals and clock in a manner similar to that

shown in Figure 4.

  Of course, the system reproduction unit must be able to reproduce the video information in the form of a signal for viewing from the recording formats at full or half-resolution on the tape of FIG. 1. Those which are Those skilled in the art will understand that the full resolution format is not a problem because the rendering unit will simply perform the inverse functions of the recording unit in the reverse order. Therefore, the transducers in the rendering unit will capture all of the video information of the tracks in the longitudinal segments of the tape and process this information in a well-known conventional manner to derive the visualization signal. With this invention, the playback unit can also reproduce the half-resolution format of a longitudinal segment of the tape.

  the same way, where the image obtained from the visualization

  This will be acceptable as in ENG (Electronic Accumulation) applications even though it is not of a quality appropriate for most studio uses. However, in the concept of a digital video hierarchy, the signal at a lower level of quality can be transcoded to a higher level of quality using well-known techniques of error compensation or concealment such as the

  interpolation scheme disclosed in US Patent No. 4,041,453.

  Thus, a hierarchy transcoder could be incorporated into the rendering unit (either separately or as part of the hiding system) to process the video information at half resolution to derive a quality viewing signal appropriate for the most part. studios. Other attempts to design such a hierarchy transcoder are described in John P. Rossi's article "A Simple Family of Digital Filters for a Binary Hierarchy" in the SMPTE Journal.

October 1981, pages 956-959.

  When using a portable unit to record video information at half resolution on a single longitudinal segment located to one side of the band of Figure 1, the other longitudinal segment placed to the other side of the band remain virgin. In order to fully utilize the tape unit and thereby improve the functional aspect of the portable recording unit, this blank portion of the tape unit is also recorded from the video information at half resolution into a tape. Another preferred embodiment of the invention is illustrated in FIG. 5.Each longitudinal segment of the strip is independently recorded or rendered in this embodiment while the strip is moving at full length and when the segment

  lengthwise to one side of the strip was recorded

  the band is "tilted" and driven in

  reverse direction to record or restore the information

  video in the longitudinal segment placed to the other side of the band. Therefore, the tracks of each longitudinal segment of the recording format of the

  Figure 5 cross the strip in different directions.

  However, the unit of the band could be

  wound up between the recording or the return of

  video information in each of its long segments

  dinals according to another embodiment of the invention, so that the tracks of each longitudinal segment pass through the band in the same direction. Furthermore, the component video information is also illustrated in the recording format of Figure 5 only as an example, and the composite video information at half resolution could easily have been recorded.

  or restored substantially in the same format.

  As the embodiments of the recording format

  of the invention, such as that shown in Figure 5, relate only to a partial resolution of the double frame, the number of transducers on the analyzer can be reduced in the equipment of the recording system and which only works with these recording formats. An example of such equipment would be a portable recording unit of an Electronic News Recording (ENG) television recorder and an analyzer for recording or rendering the format of Figure 5 in such equipment, is illustrated in FIG. Figure 6. Of course, a switching arrangement

  according to the foregoing description relating to FIG.

  will be used to direct the image elements of the Y, I and Q components to or from each of the transducers on the analyzer during recording or

restitution, respectively.

  Although only two longitudinal segments of tape

  incorporated into the multiple record formats

  Figures 1 and 5, a larger amount of such segments could be incorporated into other formats within the scope of this invention. Transducers can

  also be arranged in different ways on the

  In order to derive the various formats, the video information can be arranged in different ways for each of these formats. Examples of certain other formats within the scope of the invention are illustrated in FIGS. 7 and 8 where only one of the possible windings of the band around the analyzer and the arrangement of the transducers on the analyzer is shown for each format. For the format of FIG. 7C, pairs of tandem transducers A, B and C, D are arranged at a single location on the circumference of the analyzer as shown in FIG. 7A and are separated along the axial length of the analyzer. analyzer by a distance equal to about half

  of this length as shown in Figure 7B. The trans-

  drivers of each tandem pair explore or analyze separate tracks in the longitudinal segments on the band that is wrapped around the analyzer on about 346. For each revolution of the analyzer, each pair of tandem transducers analyzes tracks in a separate longitudinal segment, with tracks A and B arranged in one longitudinal segment of the strip and tracks C and D arranged in another longitudinal segment. for the format of FIG. 8C, the pairs of tandem transducers A, B and C, D are arranged at a first location on the circumference of the analyzer while the pairs of tandem transducers E, F and G, H are disposed at a second location on the circumference of the analyzer which is 180 from the first location, as shown in Figure 8A. The pair of tandem transducers A, B is separated, over the axial length of the analyzer, from the pair of tandem transducers C, D by a distance equal to approximately half of this axial length, while the pair of transducers in tandem E, F is separated, on

  the axial length of the analyzer, the pair of trans-

  tandem ducts G, H at a distance of about half that axial length, as shown in Figure 8B. The pairs of E, F and G, H tandem transducers should be shown in dotted lines, but because of their small size they are shown in solid lines for clarity. The transducers of each pair in tandem analyze or explore individual tracks in 2 longitudinal segments on the band that is wound on the analyzer on 180. During the initial 180 of each rotation of the analyzer, the tandem transducer

  AB first explores tracks A and B in the lower segment

  Then, the tandem transducer CD explores tracks C and D in the upper longitudinal band segment, as shown in FIG. 8C. Then, during the final 180 of each rotation of the analyzer, the EF tandem transducer

  first explores tracks E and F in the long segment

  lower dinal then the tandem transducer GH explores

  tracks G and H in the upper longitudinal segment.

  The recording formats of this invention could be used in otherwise conventional recording and / or rendering systems such as the recording system shown in Fig. 9 and the rendering system shown in Fig. 10. Both of these systems could have any desired number of runway channels, however two runway channels 1 and 2 have been

  chosen for ease of illustration.

& 610468

  In the recording system of Fig. 9, each of the Y, I, and Q components in digital form of the video signal is applied to the individual inputs of a picture element formatting means arranged according to Fig. 10 US Patent No. 4,393,414. The clock of Y in the formatter 20 is at 13.5 MHz while the I and Q clocks are at 6.75 MHz. By way of example only, an 8-bit format is used in parallel with each input of the formatting means 20. The hardware arrangement illustrated in FIG. 4 could serve as a means for formatting picture elements. having individual entries for

  each of the components Y, I and Q in a recording system.

  recording with 4 runway channels directed to each longitudinal band segment. However, it should also be understood that the recording system of Figure 9 could have only two inputs with the Y components applied to one input and the I and Q components applied to the other. In such a system, a multiplexer assembly

  in the means for formatting picture elements produced

  the necessary interface standard. The format means 20 distributes preselected combinations of picture elements of Y and / or I and / or Q to a means of

  formatting analysis 22 of the band in each channel.

  Control signals comprising the input 3.5 MHz clock, the horizontal and vertical synchronization, a signal of a vertical V / 5 or V / 6 frame portion (to allow 5 turns / frame in 525-line and 6-turn / frame television systems in 625 line television systems respectively) and a clock at the video data rate (11.8 MHz) at the output are applied to each format 22 means. which is used to convert from the video frequency to the frequency of

  band data while leaving appropriate "whites"

  required for control information of the digital video tape recorder and synchronization. For ease of illustration, all these control signals are illustrated as being applied only to channel 2 and it will be appreciated that such signals will also be applied to channel 1. As is well known, the clock at the data rate video (11.8 MHz) is determined according to the information rate of the active image plus the frequency of the digital synchronization plus the parity frequency; and horizontal and vertical synchronization redundancies are removed. The combinations of picture elements go from the formatting means 22 in each channel to an error detection and correction unit (EDAC) / parity insertion which inserts the redundancy of the computer in order to correct or detect errors in the recording or playback process, thus taking into account part of the DVTR (video tape recorder) above.The clock at the data frequency is applied to control the passage of the combinations of image elements across the unit 24 EDAC / insertion of

  parity. Then, in each channel, the combinations of

  images go from the unit 24 to a scintillation damper26 which accommodates or corrects any error in

  time basis (TBE) in the mechanics of the recording system.

  record of the video information that is recorded. As those skilled in the art know, the damper 26 contains a memory of sufficient capacity to receive the error in the time base. This memory has the clock at the data rate (11.8 MHz) which is synchronous with the received video signal, controlling its input, and a mechanical frequency clock (11.8 MHz) which is synchronous with the transport of the band, controlling its output. The parallel format of picture element combinations in each channel is

  then changed to a serial format through a conversion

  weaver 28 having the clock at the mechanical frequency applied both directly to control its input and by a multiplication unit 29 as a clock at the recording frequency to control its output. From the converter 28, the combinations of picture elements pass to a preamble and synchronization insertion unit which serves both to establish the

  departure of the exploration information and a synchronization

  numerically occupying a number of blocks per line. The clock at the recording frequency is applied to control the passage of combinations of picture elements through the unit 30. The combinations of picture elements of each channel go from the unit 30 to an encoder 32 channel used to organize the raw digital information according to the tape registration code to use. The clock at the recording frequency is applied to control the passage of information through the encoder 32. This information in each channel then passes from the encoder 32 through a conventional recording amplifier 34 to a switching unit of the encoder 32. transducer 36 to which a position signal is applied by a rotary wheel head in

  band transport 38. A number of transduc-

  Like four simple transducers at the same locations as the four pairs of tandem transducers of FIG. 8B to explore only the tracks A, E, C, G in FIG. 8C are arranged on the head wheel to direct the tandem transducers. information to the web moving at an appropriate winding angle around the wheel in the transport 38. A servo reference signal

  is applied to transport 38 by a unit of temporisa-

  40 to which sync signals are applied.

  video and position of the wheel to head and o all the clock signals, sync and signals

  vertical frame parts are provided.

  As previously mentioned, the rendering system performs the inverse functions of those of the recording system, in reverse order. Therefore, in the rendering system of Fig. 10, the information recorded on the web moving around a head wheel in a web transport 50 is captured in a serial format by a number of transducers (four in the recording system of Figure 9) which are arranged on the wheel. A unit

  transducer switch 52 distributes this information.

  to a reproduction amplifier 54 in the channels 1 and 2. A position signal is applied by the wheel to the switching unit 52. Each amplifier 54 passes the information in each channel to a decoder 56 which serves to derive raw digital information and to produce a clock signal at the frequency

  in synchronism with transport 50. The information

  In this case, the raw digital signal (always in serial format) in each channel is passed to a preamble and timing extractor 58 where the departure of the scanning information and the digital synchronization information is removed. Clock with mechanical frequency is applied to control the passage of information

  through the extractor 58 of preamble and synchronization

  tion. In each channel, a converter 60 then receives the serial bit stream and changes the serial format into image bitmap combinations in an 8-bit parallel format. The clock at the mechanical frequency is applied to the converter 60 both directly and through a division unit 61 by 8 as a clock at the reproduction frequency (11.8 MHz). The combinations of picture elements in each channel pass from the converter to a scintillation damper 62 which accommodates or corrects any time-based error (TBE) in the mechanics of the playback system with respect to the video information being rendered. This is accomplished by introducing the combinations of picture elements into

  the damper 62 with the clock at the restitution frequency

  (11.8 MHz) and output to a clock at the video data rate (11.8 MHz). Similarly, the signal differences of a time comparator 64 are individually applied to each scintillation damper62. In addition to receiving the time base error, the dampers 62 respond to signal differences in the form of programmable delays that take account of any time or mechanical errors that may occur between channels. A timing signal of each preamble and timing extractor 58 is applied to the time comparator 64 and is used therein to derive the signal differences. The combinations

  of pixels in each channel are

  62 to an EDAC 66 unit which is used to rectify the errors that can be corrected and to report detectable errors. The clock at the data rate is applied to control the passage of combinations of picture elements through the unit 66. The combinations of picture elements in each channel pass from the unit 66 to a means 68. deletion of the tape analysis format with the detectable error signal passing through a

  separate path, for example using an added bit.

  The format suppression means 68 serves to exclude additional "blanks" and converts from the frequency of the tape to the video frequency. Control signals including the clock at the input data rate, the horizontal and vertical synchronization, a V / 5 or V / 6 vertical frame portion signal and a 3.5 MHz clock at the output, are applied to each format suppression means 68. The combinations of picture elements at the output of the means 68 in each channel are passed to a picture element format suppressing means with the detectable error signal passing through. again through a separate path. The format suppression means 70 is controlled by the 13.5 MHz clock and serves to collect the combinations of picture elements from the two track channels and directs the picture elements of Y, I and Q to individual video outputs through separate error concealment means 72 such as that disclosed in US Patent No. 4,376,455 for recording composite image elements and techniques similar to those disclosed herein could be used for recording the image component elements. Between the means 70 and each concealment means 72, the detectable error signal also passes through a separate path and the 13.5 MHz clock controls the passage of the picture elements through each concealment means 72. A signal servo reference is applied by a delay unit 74 to the transport 50 of the band and with the exception of the clock at the mechanical frequency and the clock at the restitution frequency (11.8 MHz) extracted from the Channel decoder 56, the clocks, synchronization signals and frame portion signals are also derived from a timing section 74 to which the video synchronization and head wheel position signals are applied. The format deletion means 70 will contain hardware identical to that of the formatter 20 in the recording system of FIG. 9, however, the switches will be connected with the multiple inputs of the format deletion means 68 and alone

  output directed to the video outputs.

  Fig. 11 illustrates a multi-segment recording format for recording, on a magnetic tape, a television signal progressively explored or analyzed. The format separates the non-interlaced video lines 1, 2, 3, ... n ... from each frame of the television signal progressively explored into single interleaved frames A and B before recording them in different longitudinal segments. By inverting, on a frame-by-frame basis, the recording sequence of the non-interlaced video lines which are adjacent in time, the progressively-explored television signal is converted, in each longitudinal segment, to a recorded television signal having frames simple intertwined which

  produce a recorded image scene which is representative

  the full image of the whole surface, up and down, left and right, of the scene of the image contained in the original non-interlaced television signal. Thus, in each longitudinal segment of FIG. 11, one frame of the recorded television interleaved signal consists of two single interleaved frames A and B, recorded in adjacent helical channels, the single frame A being derived from a first frame of the signal non-interlaced television and the single frame B being derived from a second frame close and adjacent in time. The simple frame A, for example, will contain the odd numbered lines 1, 3, 5,

  . n ... 593, 595, ..., one is an odd integer while the simple frame B will contain even-numbered lines 2, 4, 6, ... n + 1, .. 594, 596 .. .. The resolution of the recorded image elements in each longitudinal segment is for example equal to half or a smaller fraction of the resolution of .DTD: pixels in the scene of the original image.

  FIG. 12 illustrates a recording / playback system 120, according to one aspect of the invention, that can be used for recording or reproducing a magnetic tape formatted according to the format illustrated in FIG. 11 In recording mode, for example, a non-interlaced video signal VpR is applied to a terminal 130. The VpR signal can be developed, in a conventional manner, by a progressive scanning camera system to develop, as a for example, 625 non-interlaced video lines per frame of the image,

  a recurrence frequency of 50 fields per second.

  Thus, the total number of video lines per frame of the non-interlaced video signal VpR is similar to that in a video line frame for the PAL standard. However, since the video signal VpR is non-interlaced, the frame frequency, fv is twice that of the PAL standard, while the line frequency is 2fH, also the double

  the frequency fH lines of the PAL standard.

  The video signal VpR can be either of analog or digital form, being either a monochrome signal or a color signal, and if it is a color signal, it can be either in composite or component form. On the other hand, if the video signal VpR is in component form, the components may be time division multiplexed in a single channel, for example in a MAC format or may be in a component form

  in separate channels o, for each longitudinal segment

  nal, separate transducers are assigned to each of the component signals Y, I and Q, in an analyzer arrangement similar to that of FIG. 3. If the video signal VpR is in component form with separate channels, then the processing stages shown in Figure 12 are in

double in each channel.

  In the recording mode of the recording system

  120 of FIG. 12, the levers of the recording / reproduction switches RP1 and RP2

  come into contact with the respective terminals of

  R. The non-interlaced video signal Vps passes to

a terminal 128.

  Fig. 13A shows the sequence of video line numbers for the non-interlaced video signal Vps, starting from an arbitrary number of video line n which is the same line number as that associated with the odd integer line number n in the figure 11. Because of the non-interlaced nature of the Vps video signal, the duration of a

given video line is 1 / 2fH.

  The non-interlaced video signal Vps is applied to the pole of a three-way unipolar switch S1, triggered in modulo 3 by a clock signal 2fH, ck,

  o the clock frequency of 2fH, ck is equal to 2fH.

  FIG. 13A illustrates the positions and the contact stopping times of the lever A of the switch S1 in modulo 3, r referenced on the number of the video line of the video signal Vps which is developed at the terminal 128. Thus, for example, when the video line n appears at the terminal 128, the lever Ar is in contact with the terminal D1; when the video line n + 1 appears at the terminal 128, the lever A r is in contact with the terminal D2; and when the video line n + 2 appears at the terminal 128, the lever Ar is in contact with the terminal D3. This sequence of contacts

repeats on a modulo 3 basis.

  The contacts D1-D3 are coupled to respective first ends of memories Mi-M3, each memory having a capacity for storing the value of a line of picture elements according to a desired desired resolution of the picture elements. The other respective ends of the memories M1-M3 are connected to the respective contacts C1-C3 of a bipolar switch S2 which comprises a lever Ap coupled to a pole P and a lever Aq coupled to a pole Q. The levers of the switch S2 are driven by counter-clockwise rotation in modulo 3 by the clock signal fH, ck produced by

timing unit 122.

  A two-pole bipolar switch S3 has a pole R coupled to the pole P of the switch S2 and a pole S coupled to the pole Q of the switch S2. The levers of the switch S3 operate between their solid contact positions and their dotted contact positions at the frame rate of the non-interlaced video signal VpS according to the clock fv, ck. Thus, for example, during the appearance of the video lines of the frame 1 of the non-interlaced video signal VpS, the levers of the switch S3 are at their full line contact position; At the next frame, Frame 2, the levers are in their dotted position. Therefore, during Frame 1, the video signal V1, developed at the contact terminal B1 of the switch S3 is equal to the video signal Vp, developed at the pole P of the switch S2 and the video signal V2, developed at the contact terminal B2 , is equal to the video signal V q developed in the pale Q of the switch S2. The opposite situation

  is true during the next frame, Frame 2.

  Each of the memories M1-M3 can be organized under

  the form of a FIFO (FIFO) memory.

  Each memory is capable of signal flow in each direction relative to the input / output operation according to the particular internal clock configuration read / write in the memory. For example, each of the memories may comprise two parallel delay lines operating in ping-pong or in switching between the read and write functions by means of multiplexer guide stages coupled to both ends of each delay line. . In the recording mode of the system of FIG. 12, the ends of the memories M1-M3 coupled to the respective terminals D1-D3 serve as signal inputs while the other ends of the memories coupled to the respective terminals C1-C3 serve as outputs.

of memory.

  To introduce samples of the signal into the memories M1-M3, a delay unit 122 applies a write clock signal WR1, ck to the memory M1, a write clock signal WR2, ck to the memory M2 and a write clock signal WR3, ck to the memory M3. In order to extract the samples from the memories M1-M3, the delay unit 122 applies a read clock signal Ri, ck to the memory M1, a read clock signal R2, ck to the memory M2 and a signal d read clock R3, ck to the memory M3. The non-interlaced video signal VpS

  terminal 128 is applied in the recording mode.

  the timing unit 122 for synchronizing the production of the write and read clock signals on the sequence of the video lines 1, 2, 3 ... n, ... of the non-interlaced video signal Vps and for synchronizing, in phase and in frequency, the signal 2fH, ck and the signal fH, ck and a signal fv, ck on the horizontal and vertical erasing intervals associated with the signal

non-interlaced video Vps.

  Figs. 13C-13E illustrate the contents of memories M1-M3 as a function of the video line number in the non-interlaced video signal Vps. When the line n of the video signal Vps appears at the terminal 128 and the lever Ar of the switch S1 remains in the contact D1, the line n is introduced in the memory M1. Line n remains in memory M1 during the next two non-interleaved lines, while lever Ar remains sequentially at contact terminals D2 and D3. When the line n + 1 of the video signal Vps appears at the terminal 128, the lever Ar remains at the contact terminal D2 and the line n + 1 is introduced into the memory M2 by its respective write clock. The line n + 1 remains in the memory during the next two non-interleaved lines, while the lever Ar remains sequentially at the contact terminals D3 and Di. When the line n + 2 of the video signal Vps appears at the terminal 128, the lever Ar remains at the contact terminal D3 and the line n + 2 is introduced into the memory M3 by its respective write clock. The line n + 2 remains in the memory M3 during the two following non-interlaced lines, while the lever Ar remains sequentially at the contact terminals D1 and D2. The cycle in modulo 3 of the switch S1 is repeated, the line n + 3 being introduced into the memory M1 when the lever A remains at the terminal r

contact D1.

  The signals stored in the memories MI-M3 are sequentially extracted from the memories in coordination with the rotation of the levers A and A between the contacts C1-C3 p q of the switch S2. The read frequency of each memory is equal to half of the write frequency and the value of a line of the memory is extracted in an interval 1 / fH, which interval is equal to the stopping time at each of the terminals. C1-C3 of each lever,

  Ap and Aq, as shown in Figures 13F and 13G.

  During the synchronized reading of the memories M1-M3, the line n stored in the memory M1 and the line n + 1 stored in the memory M2 are extracted by the respective read clocks when the lever A remains at the contact terminal C1 and that the lever Aq remains at the contact terminal C2 as shown in FIGS. 13F-13I. For a good reading, the synchronized operation is such that the stop times at the contacts C1 and C2, to read the stored lines n and n + 1, occur during the sequential appearance at the terminal 128 of the lines n + 2 and n +3 of non-interlace video signal Vps

of Figure 13A.

  At the next position of the levers of the switch S2, the lever A remains at the contact terminal C3 and the lever p Aq remains at the contact terminal C1. At this position, the stored line n + 2 is extracted from the memory M3 and the stored line n + 3 is extracted from the memory M1. In the sequential final position of the S2 switch contacts, for a given cycle in modulo 3, the lever A remains at P

  contact terminal C2 and lever A remain at terminal C3.

  q10 The stored line n + 4 is thus extracted from the memory M2

  and the stored line n + 4 is thus extracted from the memory M23.

  and the stored line n + 5 is extracted from the memory M3.

  As a result of the synchronous operation described above of switches S1-S3 and memories M1-M3, the non-interlaced video signal Vps is converted into two separate interleaved video signals V1 and V2. At frame 1 of the non-interlaced video signal VpS, the interlaced video signal V1

  contains the odd numbered lines of the frame, that is,

  say single frame A and interlaced video signal V2 contains even number lines, i.e., single frame B. For frame 2 of non-interlaced video signal Vps, when the switches of switch S3 are in positions in dashed lines shown in FIG. 12, the interlaced video signal V1 contains the video lines of the single frame B and the interlaced video signal V2 contains the lines of the single frame A. The interlaced video signal is applied to an electronic stage 126 of FIG. recording / playback and signal

  video V2 is applied to an electronic stage 127 of recording.

  recording / retrieval, both operating in

  recording to develop the interlaced video signal Vi and the interlaced video signal Vi2, respectively. The video signals V1 and Vi2 are suitably packaged for recording on the respective longitudinal segments 1 and 2 of the magnetic strip of FIG. 11 by means of an analyzer apparatus comprising stages

  respective transducers of analyzer 123 and 124.

  The construction of the analyzer apparatus 129 is similar to that of the analyzer apparatus illustrated in FIG. 3, with the lower level transducers Y1, Y3, I1, Q1 'associated with the transducer stage 123 of FIG. transducers of the upper level Y2 '

  Y4 and I2 'Q2' associated with the transducer stage 124.

  The tape winding angle for the analyzer apparatus 129 may be similar to the omega winding at a winding angle close to 360 shown in Fig. 3 or may be a full winding angle at 360

  which is formed by an alpha winding configuration.

  The bidirectional flow of the control signals is produced between the delay element 122 of the

  Figure 12 and an analyzer control stage and asser-

  the operation of the capstan 125 which controls the recording and playback of the reference and control pulses of the head wheel which can be associated in a conventional manner with the analyzer apparatus 129, the tracks of which are not illustrated on Figure 11. In Figure 11 are also not shown the tracks

separate audio, if there is one.

  In order to reproduce the non-interlaced video signal Vps which is recorded on the magnetic strip of FIG. 11, the recording / reproduction system 120 of FIG. 12 operates in the playback mode with the levers of the switches RP1 and RP2 in contact with the terminals.

  respective refunds PB. The heads of the trans-

  conductors 123 and 124 of the analyzer apparatus 129 pick up the signal in the recorded tracks of each of the respective longitudinal segments 1 and 2 to produce a signal flow from the analyzer 129 to the terminal 128 which is essentially the inverse of the signal flow described when the recording / playback system 120

  was in recording mode. Synchronous operation

  switches S1-S3 and memories M1-M3 is essentially the same in the playback mode as in the previously described recording mode and thus a

  description of the operation will not be repeated.

  The interlaced video signals V il and Vi2, detected on the respective longitudinal segment tracks by the transducer stages 123 and 124, are combined into non-interlaced video sequence lines of a video signal.

  reconstructed non-interlace Vps that appears at terminal 128.

  The vertical and horizontal synchronization components are inserted into the non-interlaced video signal developed at terminal 128 by a timing generator 121 which receives the vertical and horizontal timing information from timing unit 122, according to the track information. control and / or cue track produced by the control stage 125. In this way, a non-interlaced reconstructed video signal Vps with full horizontal and vertical synchronization information is developed by the recording / playback system 120 at the same time. now output signal line 130 recorded tracks of the two segments

  longitudinal lines 1 and 2 in FIG.

  When using a portable unit to restore the recorded magnetic stripe of Fig. 11, a recording / playback system may be used which has an analyzer apparatus which is capable of and analyzes tracks in only one of the longitudinal segments, such as

  than the Longitudinal Segment 1 of Figure 11 (a). The apparent

  The analyzer in the portable rendering unit may be equipped with fewer transducers than is required to retrieve only one of the longitudinal segments in an arrangement of a transducer.

  analyzer similar to that shown in Figure 6.

  The rendering unit will produce an interlaced video signal such as the interlaced video signal Vi of Fig. 12, which can then be directly applied to a sync generator for insertion of the sync information to develop an interlaced signal of

  television restitution. The interlaced signal of restitution

  The television arrangement contains interlaced video lines that are representative of the entire scene area of the image contained in the recorded non-interlaced video signal, represented by all of all tracks in both segments of the magnetic stripe of FIG. Therefore, the rendering unit advantageously offers easy conversion of a progressively explored television format to an interlaced exploration television format without the use of single frame storage size memories. In compromise, the resolution of the interlaced video signal, obtained when only one longitudinal segment of the magnetic strip of FIG. 11 is rendered, is coarser, since the resolution is equal to half the resolution of the picture elements. video signal

  non-interlace origin, in the vertical direction.

2610468 '

Claims (6)

R E V E N D I C A T I 0 N S   1.- Recording system for recording,   on a magnetic tape, a digital television signal   vision containing a picture frame formed of picture elements of the information, characterized by a number of transducers (123, 124) arranged to explore a number of helical tracks on said magnetic strip in a number of segments longitudinal stripes which divide the width of said strip along its length; an input terminal (130) receiving said television signal; means (S1, S2, S3) coupled to said input terminal for directing respective image elements to respective transducers; control means (122) coupled to said means for directing and responding to the timing information of said television signal for synchronously controlling said means for directing recorded video lines in each of said longitudinal tape segments; which form, in each band segment, a recorded picture scene representative of the entire surface of the picture scene contained in said television signal and formed of a number of recorded picture elements having a resolution of picture elements which is a smaller fraction of the picture element resolution of the picture scene contained in said television signal; and said control means responds to the information of   horizontal synchronization (128) of said television signal   vision for recording picture elements of each video line of said television signal in each of said longitudinal strip segments so as to reduce the   number of picture elements in each video line recorded   relative to the number of picture elements available in a corresponding video line of said television signal. 2.- Tape restitution machine for obtaining a reproduced television signal from a recorded magnetic tape of a digital television signal containing   an image scene formed of image elements of information   recording, on said magnetic strip, a number of helical tracks in a number of longitudinal strip segments which divide the width of said strip along its length, so that pixels of each video line of said signal digital television signals are recorded in each of said longitudinal band segments so as to produce, in each band segment, a recorded picture scene representative of the entire surface of the picture scene contained in said digital television signal and formed of a number of recorded image elements having a resolution of the recorded image elements which is a smaller fraction of the resolution of the image elements of the image scene contained in said digital television signal, characterized in that it comprises an analyzer (129) with a transducer means   (123, 124), which explores the tracks   stored on said magnetic tape to obtain said television playback signal which contains a television playback picture scene representative of the entire surface of said picture scene, said analyzer operating in at least one reduced resolution mode for exploring the recorded tracks placed in at least one but not all of the amount of longitudinal segments for recovering said television signal at a resolution of the pixels of said least fraction, or a full resolution mode for exploring the recorded tracks placed in each of said longitudinal band segments for recovering said television signal at the same resolution as the recorded picture elements.  3.- Recording system for recording, on a magnetic tape, video lines of a television signal containing an image scene formed of picture elements of the information, characterized by a number of transducers (123, 124) arranged to explore a number of helical tracks on said magnetic tape in a number of longitudinal strip segments which divide the width of said strip along its length; an input terminal (130) for receiving said television signal; means (S1-S3) coupled to said input terminal   to direct respective video lines to trans-   respective ductors; and control means (122, M1-M3) connected to said means for directing and responding to the timing information of said television signal for synchronously controlling said means for directing to record in each of said longitudinal band segments , the recorded video lines which produce, in each band segment, a recorded picture scene representative of the entire surface of the picture scene contained in said television signal and having a pixel resolution which is a lesser fraction of the resolution of the image element of the image scene contained in said television signal; and said control means responds to the horizontal synchronization information (128) of said television signal for sequentially recording video lines of said television signal which are adjacent in time to corresponding and adjacent segments   among said longitudinal strip segments.   4.- Tape rendering machine for obtaining a signal of reproduction of a recorded magnetic tape of video lines of a television signal containing an image scene formed of information image elements, of the type o on said magnetic tape are recorded a number of helical tracks in a number of longitudinal strip segments which divide the width of said strip along its length, so that some of the picture elements are recorded in some of the longitudinal strip segments in a manner which records, in each of said longitudinal strip segments, recorded video lines which produce in each band segment a recorded picture scene representative of the entire surface of the picture scene contained in said television signal and having a resolution of the recorded image elements which is a lesser fraction of the resolution of the image elements of the scene image contained in said television signal, where the video lines of said television signal which are adjacent, in time, are recorded in sequence in corresponding and adjacent segments of said longitudinal strip segments, characterized in that: said machine method includes an analyzer (129) having a transducer means (123, 124) thereon and exploring the tracks recorded on said magnetic tape to obtain said playback signal which contains a reproduction image scene representative of the entire surface of the television signal image scene, said analyzer operating in at least one of a reduced resolution mode to explore the recorded tracks that are placed in at least one   one, but not all, of these longitudinal segments   band dinners for recovering said television signal at a resolution of the picture elements of said least fraction, and a full resolution mode for exploring the recorded tracks placed in each of said longitudinal strip segments for recovering said television signal at the same element resolution recorded images.   5. A recording system for recording on magnetic tape non-interlaced video lines of a progressively explored television signal, characterized by: a number of transducers (123, 124) arranged to explore a number of tracks helical on said magnetic tape in a number of longitudinal strip segments which divide the width of said tape along its length; an input terminal (130) receiving said non-interleaved video lines, means (S1-S3) coupled to said input terminal for directing respective portions of said signal   progressively explored from television to trans-   respective ductors; control means (122, M1-M3) coupled to said means for directing and responsive to the timing information of said progressively-explored television signal for synchronously controlling said means for directing to record said non-interlaced video lines of said television progressively explored in corresponding segments of said longitudinal band segments so as to produce, in a given segment, a recorded interlaced signal of TV.   6.- Tape restitution machine for obtaining a television reproduction signal from a recorded magnetic tape of non-interlaced video lines of a progressively explored television signal, of type o are recorded on said magnetic tape, a number helical tracks in a number of longitudinal band segments which divide the width of said band along its length, so that a given double frame of said progressively scanned television signal is recorded as a number of single frames of recorded video lines which are recorded in different segments of the longitudinal band segments to produce, in a given segment, a recorded television interlaced signal, characterized in that it comprises an analyzer (129) with a transducer means (123) , 124) which is placed there, which explores tracks recorded on said magnetic tape, said an analyzer operating in at least one interleave mode for exploring recorded tracks placed in said given segment to retrieve said television rendering signal as an interlaced television signal, or a non-interlaced mode for exploring the stored tracks placed in each of said longitudinal segments of   tape to retrieve the retransmission signal from   vision in the form of a progressive television signal   explored with non-interlaced video lines.